The present invention relates to the field of floor sanders, and more particularly, relates to a rotary floor sander for use in sanding or finishing floors.
It is desirable in modern construction practice that wooden floors be finished to a relatively smooth, flat surface. Moreover, it is known in the prior art to employ sanding devices to mechanically assist in such efforts. For efficient operation, such devices typically utilize disposable abrasive media, i.e. abrasive-coated paper or fabric, in belt, disc or sheet form.
An example of a prior art sanding device of this general type which utilizes disposable abrasive media in belt form is shown in U.S. Pat. No. 5,575,710 (Kramer), issued Nov. 19, 1996. This type of sanding device is known to be relatively reliable in operation, and to be relatively effective in material removal. However, this type of sanding device suffers in that, in order to avoid undulations in the floor surface, operators are required to exercise significant skill and dexterity. Further, abrasive belts are typically fairly expensive to purchase. As well, this type of sanding device is unable to effectively sand close up to walls or other protrusions.
An example of a prior art sanding device which utilizes disposable abrasive media in disc form is shown in U.S. Pat. No. 5,890,954 (Barous), issued Apr. 6, 1999. This general type of sanding device is known to be relatively reliable in operation, and to be effective in material removal. Further, this type of sanding device is known to overcome the shortcomings inherent in belt-type sanders, in that sanding can be effected relatively close to walls or other protrusions, and moreover, undulations in the floor surface may be avoided by the exercise of relatively modest amounts of skill, concentration and dexterity. However, this type of sanding device suffers in that replacement of the abrasive discs, which are relatively expensive to purchase, is relatively cumbersome and time-consuming, and typically requires the operator to physically remove and replace, through the use of hand tools, a bolt which retains the abrasive disc in position. As well, this type of sanding device is intended for use by an operator in a kneeling or stooped position, and as such, it is unsuited for use in sanding large expanses of floor surface. Additionally, this type of sanding device is known to release significant quantities of dust into the surroundings, despite the vacuum system provided therewith.
An example of a prior art sanding device which utilizes disposable abrasive media in sheet form is shown in U.S. Pat. No. 3,638,362 (Stoll), issued Feb. 1, 1972. This type of sanding device is known to be relatively reliable in operation, and is known to overcome many of the shortcomings inherent in disc and belt sanders, in that undulations in the floor surface will, for practical purposes, result only from carelessness in operation, and moreover, replacement of the abrasive sheets, which are relatively inexpensive to purchase, is relatively quick and simple. As well, sanding may be effected close to walls and other protrusions. However, this type of sanding device, which relies upon vibratory or orbital action of the abrasive surface, is known to be relatively slow and ineffective in material removal, and as such, unsuited for use in sanding large expanses of floor surface.
It is an object of the present invention to overcome, inter alia, the shortcomings of the prior art by providing a floor sander that is reliable in operation; that does not demand unduly onerous levels of skill, dexterity or concentration from the operator to achieve a relatively smooth, flat finish; that utilizes inexpensive sheets of abrasive media; that enables abrasive exchange to be conveniently accomplished without the use of hand tools; which has practical utility in applications which require large expanses of floor surface to be sanded; which releases relatively modest amounts of dust into its surroundings in use; and which has practical utility in application wherein floor sanding operations must be effected close to walls or other protrusions.
These and other objects are addressed by the present invention, a rotary floor sander.
In accordance with a first aspect of the invention, the rotary floor sander is for use with one or more sheets of flexible sanding media each having a first portion, a second portion, a smooth side and an abrasive side, and comprises a platform. The platform has a rearward end and a forward end and defines a longitudinal axis extending between the rearward end and the forward end. Two or more wheels are mounted on the platform adjacent to the rearward end for rotation about a lateral axis extending substantially normal to said longitudinal axis. The wheels are operatively positioned upon the floor surface so as to support the rearward end of the platform for rolling movement substantially parallel to the longitudinal axis. A sanding head member is also provided. The sanding head member defines a substantially planar sanding face, and is mounted on the platform for rotation about a substantially vertical axis with the sanding face being oriented substantially normal to the substantially vertical axis and substantially parallel to the floor surface. A drive means is mounted on the platform for driving said rotation of the sanding head member about the substantially vertical axis. Additionally, an attachment means is provided for selectively, releasably attaching one or more sheets of said flexible sanding media to the sanding head member for rotation therewith, with the smooth side of each of said sheets in contactable relation to said sanding face and with the abrasive side of each of said sheets in contactable relation to said floor surface. A handle means is also provided, rigidly mounted to the platform, adjacent to the rearward end thereof, and oriented substantially upwardly and rearwardly.
According to another aspect of the invention, the rotary floor sander preferably comprises a positioning means for selective movement of each of the wheels between a fully raised position, whereat the rearward end of the platform is relatively proximal to the floor surface, and a fully lowered position, substantially downwardly disposed from the fully raised position, whereat the rearward end of the platform is relatively distal to the floor surface. The positioning means further provides for selective movement of each of said wheels between a rearward position, whereat said each wheel is relatively proximal to the rearward end of the platform, and a forward position, substantially longitudinally forwardly disposed from the rearward position, whereat said each wheel is relatively distal to the rearward end of the platform.
According to another aspect of the invention, the attachment means preferably comprises one or more elongate slots defined in the sanding face, each of the elongate slots being shaped and dimensioned for releasable extension therethrough of the first portion of a respective one of the sheets of flexible sanding media.
According to another aspect of the invention, each elongate slot is preferably aligned substantially tangentially to an arc of rotation defined by the substantially vertical axis.
According to other aspects of the invention, the rotary floor sander preferably further comprises a downwardly-depending housing member mounted on the platform and defining a downwardly-opening chamber, and a skirt member mounted on the housing member and defining a chamber extension contiguous with said chamber, said skirt member being mounted for movement substantially parallel to the substantially vertical axis between a lowered position, whereat the chamber and chamber extension collectively operatively enclose said sanding head member and said one or more sheets of flexible sanding media, and a raised position, substantially vertically upwardly disposed from the lowered position. A vacuum means is additionally provided, in operative fluid communication with said chamber.
According to one further aspect of an alternative embodiment of the present invention, the rotary floor sander is for use with one or more sheets of sanding media, each of said sheets having a smooth side and an abrasive side, and comprises a platform. The platform has a rearward end and a forward end and defines a longitudinal axis extending between the rearward end and the forward end. Two or more wheels are mounted on the platform adjacent to the rearward end for rotation about a lateral axis extending substantially normal to said longitudinal axis. The wheels are operatively positioned upon the floor surface so as to support the rearward end of the platform for rolling movement substantially parallel to the longitudinal axis. A sanding head member is also provided. The sanding head member defines a substantially planar sanding face, and is mounted on the platform for rotation about a substantially vertical axis with the sanding face being oriented substantially normal to the substantially vertical axis and substantially parallel to the floor surface. A drive means is mounted on the platform for driving said rotation of the sanding head member about the substantially vertical axis. Additionally, an attachment means is provided for selectively, releasably attaching one or more sheets of sanding media to the sanding head member for rotation therewith, with the smooth side of each of said sheets in contactable relation to said sanding face and with the abrasive side of each of said sheets in contactable relation to said floor surface. A handle means is also provided, rigidly mounted to the platform, adjacent to the rearward end thereof, and oriented substantially upwardly and rearwardly.
Other advantages, features and characteristics of the present invention, as well as methods of operation and functions of the related elements of the structure, and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following detailed description and the appended claims with reference to the accompanying drawings, the latter of which is briefly described hereinbelow.